Nuclear Site Drives Chromium Underground for Clean Up

In Richland, Wash., a new test project at the Hanford Nuclear site is contaminating groundwater with chromium in hopes to speed up an expected 50-year cleanup process.

According to the Tri-City Herald, the chromium is driven into the groundwater aquifer after which it is then pumped out before reaching the Columbia River. It is then treated and injected back into the groundwater aquifer. Chromium can cause cancer in people, and can be harmful to salmon and other aquatic life in the Columbia River, even when it is at levels that meet drinking water standards, according to Tri-City Herald.

“We’re flushing contamination out of the soil that would take decades to slowly come down [to groundwater],” said Mike Cline, the Department of Energy Hanford project director for soil and groundwater, according to the Tri-City Herald.

In November of 2016, a piece from NBC News was published claiming the site was “the most toxic place in America.” The site produced plutonium for American’s nuclear arsenal 70 years ago, according to NBC. Its contractor, Washington River Protection Solutions, is managing a $110 billion cleanup of 56 million gal of chemical and nuclear waste contained in 177 underground tanks. According to NBC, this task is expected to last for the next 50 years.

Now, the contaminated water is pumped and cleaned before the groundwater flows into the Columbia River, according to Tri-City Herald. The Department of Energy is using multiple techniques to remove hexavalent chromium in groundwater at Hanford.

First, it dug up contaminated soil, which in some cases reached groundwater in areas near the Columbia River that are known for heavy contamination. This aimed to prevent chromium from migrating deeper into the soil, according to Tri-City Herald. The DOE also pumped and treated groundwater at locations where it is contaminated. According to Tri-City Herald, the chromium is stripped from the water and the clean water is reinjected into the ground.

By 2015, the plants cleaned up most of the plume near the two reactors and were shut down, according to Tri-City Herald.

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